Aperture Area Reduction in Planar Microstrip Phased Arrays of Small Wideband Patch Elements

In this paper we present a systematic characterization of planar microstrip phased arrays, in various lattice arrangements, with the objective of aperture area reduction. The antenna element design avoids sophisticated prototyping and can be used to design small antennas ( $0.6\leq ka\leq 1.4$ ) with $\geq 30\%$ impedance bandwidth. Investigation of phased arrays, composed of the designed antenna elements, show that a transformation from a square-grid-rectangular-aperture to triangular-grid-hexagonal-aperture leads to $28.68\%$ aperture area reduction without proportionate reduction in gain ( $6.1\%$ ). The planar arrays of all configurations are shown to be free of scan blindness over the angular range of ±45° from boresight, in the principal E- and H-planes.